Display devices each including a display section and an input section which are integrated with each other in order to downsize the devices have been recently widespread. Particularly for portable terminals such as mobile phones, PDAs (Personal Digital Assistants), and notebook personal computers, there are widely employed display devices each including a touch panel which, when a finger or a stylus (detection target) touches a surface of a display, is capable of detecting a position where the finger or the stylus touches.
Touch panels of various types such as a so-called resistive film (pressure-sensitive) type and a capacitive type are conventionally known. Among them, capacitive touch panels are widely employed.
In the capacitive touch panels, a position where a finger or a stylus touches is detected by detecting a change in capacitance when the finger or the stylus touches a display screen. This allows detecting, with a simple operation, the position where the finger or the stylus touches.
In many cases, so-called sensor electrodes which are position detecting electrodes for detecting a position where an object touches are made of, for example, ITO (indium tin oxide). However, in a case of a touch panel having a large screen, a sensor electrode made of ITO has large resistance, so that detection sensitivity unfortunately drops.
Patent Literatures 1 and 2 each describe a configuration in which a sensor electrode is constituted by lattice-shaped metal wires so as to reduce resistance of the sensor electrode. In order that sensor electrodes extending in a longitudinal direction and sensor electrodes extending in a lateral direction do not overlap each other, the sensor electrodes are each constituted by a plurality of lattice electrodes each defined to have a square shape.